Abstract:

Drive comprising a housing with a drive unit. The drive unit comprises an
electric motor and a drive train comprising a reduction stage with an
output shaft. The drive comprises an evoloid gear stage and a cover
module which comprises a drive stage to be coupled with the output shaft
of the drive train. The evoloid gear stage is preferably designed as a
pinion with a toothing which comprises less than six, preferably two or
three, teeth.

Claims:

1. A drive comprising a housing with a drive unit comprising:an electric
motor; anda drive train which comprises a reduction stage with an output
shaft, an evoloid gear stage and a cover module which comprises a drive
stage cooperating with the output shaft of the drive train.

2. The drive according to claim 1, wherein the evoloid gear stage
comprises a pinion with a toothing of less than six teeth.

3. The drive according to claim 1, wherein the drive stage of the cover
module comprises a single transmission.

4. The drive according to claim 1, wherein the drive stage is one of an
acceleration stage, a reduction stage and a linear stage.

5. The drive according to claim 1, wherein the cover module forms an
auxiliary cover for the housing.

6. The drive according to claim 1, wherein the housing comprises at least
two parts which are each provided with a number of attaching eyes.

7. The drive according to claim 6, wherein the cover module is provided
with attaching eyes which are aligned with the attaching eyes of the
housing.

8. The drive according to claim 6, wherein the at least two housing parts
and/or the cover module mutually cooperate via a snap connection.

9. The drive according to claim 1, wherein the drive further comprises a
potentiometer in the housing for the purpose of a memory function.

10. The drive according to claim 1, wherein the drive train further
comprises a slip coupling.

11. The drive according to claim 1, wherein the housing is arranged for
receiving electric motors of different size.

12. A drive system comprising a housing with a drive unit comprising an
electric motor and a drive train which comprises a reduction stage with
an output shaft, wherein the drive train comprises an evoloid gear stage
and wherein on the housing a cover module can be placed which comprises a
drive stage to be coupled with the output shaft of the drive train, and
wherein the cover module can be selected from a group of cover modules
having mutually different drive stages.

13. The drive according to claim 1, wherein the evoloid gear stage
comprises a pinion with a toothing of three teeth.

14. The drive according to claim 1, wherein the evoloid gear stage
comprises a pinion with a toothing of two teeth.

Description:

[0001]The invention relates to a drive comprising a housing with a drive
unit provided with an electric motor and a drive train which comprises a
reduction stage with an output shaft.

[0002]Such a drive is frequently used for opening and closing a car side
window or a car rear window, or for operating window covering, such as
for instance a sunshade.

[0003]A drawback of such a drive is that for each application an adapted
housing needs to be made. Moreover, such a drive usually has a complex
transmission.

[0004]The invention contemplates a drive of the type mentioned in the
opening paragraph that obviates at least one of the disadvantages
mentioned.

[0005]To this end, the invention provides a drive comprising a housing
with a drive unit comprising an electric motor and a drive train which
comprises a reduction stage with an output shaft, characterized in that
the drive train comprises an evoloid gear stage and a cover module which
comprises a drive stage coupled with the output shaft of the drive train.

[0006]By providing the housing with a cover module having a drive stage
coupled to the output shaft, it is possible in a simple manner to adapt
the drive to the application. Depending on the application, only a
different cover module with drive stage coupled to the output shaft is
needed. The cover module with drive stage can thus be especially adapted
to the intended application, without this requiring a completely new
housing. Thus the housing having the drive unit therein can remain
substantially unaltered and the drive can be easily adapted to the
application by making use of a different cover module.

[0007]By use of an evoloid gear stage, a high transmission can be realized
in a single transmission stage.

[0008]By the use of the cover module with a drive stage coupled to the
output shaft and an evoloid gear stage in the drive, the drive can be
made of simple and inexpensive design. Also, a high efficiency can be
achieved, so that the drive can easily be deployed for various
applications.

[0009]An evoloid toothing in a pinion as a driving gear of the evoloid
gear stage in this context is understood to be a pinion with a toothing
according to DIN 3960, wherein [0010]the number of teeth is less than
6, preferably 2 or 3; [0011]the tooth angle is greater than 15°;
[0012]the profile correction of the pinion is greater than 0.5; [0013]the
profile correction of the main gear is less than or equal to 0; [0014]the
tooth root height factor of the main gear is greater than or equal to the
tooth head height factor of the pinion; and [0015]the tooth head height
factor of the main gear is substantially equal to the tooth root height
factor of the pinion.Such an evoloid toothing is discussed in more detail
by K. Roth in Zahnrad Technik--Evolventen Sonderverzahnungen, Springer
Verlag ISBN 3-540-64236-6.

[0016]By providing a cover module as an auxiliary cover for the housing,
in case of a different application it is merely required to place an
adapted auxiliary cover on the housing. Thus, the housing can be supplied
as a whole, possibly with its own cover, after which a different
auxiliary cover can be placed on it, depending on the application.

[0017]By providing the cover module with attaching eyes which are aligned
with attaching eyes of the housing, the parts can simply, rapidly and
easily be connected with each other. Also, at the same time the parts are
properly positioned with respect to each other. Advantageously, use can
thus be made of the attaching eyes of the housing for easy expansion of
the housing.

[0018]By arranging the housing of the drive for receiving electric motors
of different size, for instance by providing a stop in the housing, the
housing can be easily and inexpensively used in different applications.

[0019]The invention also relates to a drive system.

[0020]Further advantageous embodiments of the invention are represented in
the subclaims.

[0021]The invention will be elucidated on the basis of exemplary
embodiments which are represented in a drawing. In the drawing:

[0022]FIG. 1 shows a schematic perspective view of a first embodiment of a
drive according to the invention in disassembled condition.

[0023]FIG. 2 shows a schematic perspective disassembled bottom view of a
second embodiment of a drive according to the invention in disassembled
condition.

[0024]FIG. 3 shows a schematic perspective disassembled top plan view of
the embodiment of FIG. 2.

[0025]It is noted that the drawing figures are only schematic
representations of a preferred embodiment of the invention which is
described by way of non-limitative exemplary embodiment. In the drawing
figures, the same or corresponding parts are indicated by the same
reference numerals.

[0026]FIG. 1 shows a drive 1 which comprises a housing 2. The housing 2 in
this exemplary embodiment comprises two housing parts 2a and 2b, of which
the housing part 2a serves as cover for housing part 2b. In the housing
part 2b, in the space 3, an electric motor--not shown--can be
accommodated.

[0027]The housing 2 is provided with a cover module 10 which in this
exemplary embodiment is designed as an auxiliary cover 10.

[0028]However, the housing 2 can also be designed as the housing part 2b,
without the cover 2a, with the cover module 10 then functioning as cover
for the housing part 2b.

[0029]The drive 1 comprises a drive train 4, with the stages 4a and 4b
shown in this exemplary embodiment. The stage 4a cooperates with a worm
mounted on the output shaft of the electric motor--not shown here--and
comprises a pinion 7. The pinion 7 has an evoloid toothing which
cooperates with an evoloid main gear on the stage 4b. By the use of an
evoloid toothing, in one transmission stage a high transmission ratio can
be realized. Preferably, the evoloid pinion 7 has only two or three
teeth. In FIG. 1 it can be seen that the evoloid pinion 7 in this example
has two teeth.

[0030]The drive train 4, in this example comprising the stages 4a and 4b,
is situated between the housing parts 2b and 2a. The housing parts 2a, 2b
together with the electric motor and the drive train 4 form a basic unit
20.

[0031]The output shaft 5 of the drive train 4 in this exemplary embodiment
cooperates with a drive stage 9 of the cover module 10. The drive stage 9
of the cover module 10 in FIG. 1 comprises a single transmission. In FIG.
2 the drive stage 9 of the cover module 10 is designed as a linear
transmission. However, the drive stage 9 may also be designed as a
reduction stage or an acceleration stage. Thus, on the housing 2 a cover
module 10 can be placed which can be coupled to the output shaft 5 of the
drive train 4, and which can be selected from a group of cover modules 10
having mutually different drive stages 9. The drive stage 9 cooperates
with the cover module 10, and may for instance be carried by the cover
module 10. In FIG. 1 it can be seen that a projection 15 of the drive
stage 9 cooperates with a hole 16 in the auxiliary cover 10. In FIGS. 2
and 3 a toothing 17 of the drive stage 9 cooperates via a guide 18 in the
auxiliary cover 10 with the output shaft 5 of the drive train 4.

[0032]The two parts of the housing 2, being the housing parts 2a and 2b,
are provided with a number of mutually aligned attaching eyes 11a and
11b. Through the mutually aligned attaching eyes 11a and 11b, the housing
parts 2a and 2b can be simply and rapidly coupled to each other, while at
the same time a proper positioning of the two housing parts 2a and 2b
with respect to each other can be achieved.

[0033]Optionally, the housing parts 2a and 2b may also be provided with a
snap connection 13, 14, so that the housing parts 2a and 2b can remain
firmly coupled with each other.

[0034]As can be seen in FIG. 1 and FIG. 2, the cover module 10 is also
provided with attaching eyes 12, which are aligned with the attaching
eyes 11a and 11b of the housing 2. By providing attaching eyes 11a, 11b,
12, an extra part--in this case auxiliary cover 10--can be easily placed
on the housing 2 while use can be made of the attachment means already
present on the housing 2. Also, at the same time, the cover module 10 is
properly positioned with respect to the housing 2. The housing 2 is
readily expandable in this way.

[0035]As the housing 2 is designed as two housing parts 2a and 2b which
can be solidly connected with each other through attaching eyes and snap
connection, such a housing can be prefabricated in large numbers, so that
a drive with such a housing can be made of inexpensive design. Depending
on the desired application, a different cover module 10 can then be
mounted on the housing 2. This makes the drive 1 modular and suitable for
a variety of applications.

[0036]The housing 2 together with the drive train 4 and the electric motor
forms a standard basic unit 20, on which, depending on the application, a
different cover module 10 with adapted drive stage 9 can be placed.

[0037]The housing 2 may be designed for receiving electric motors of
different size. For this purpose, in the housing part 2b for instance a
stop may be provided or a chamber in which a smaller electric motor could
fit. Also, the coupling parts 15 of the housing part 2a that cooperate
with the electric motor may be placed such that they can cooperate with,
for instance, a smaller electric motor.

[0038]In the housing 2, further, a potentiometer may be provided for the
purpose of a memory function. This may for instance be favorable when
operating window covering, such as sunshades or curtains.

[0039]Also, the drive train 4 can comprise a slip coupling.

[0040]It will be clear that the invention is not limited to the exemplary
embodiments represented here. Thus, the housing can optionally consist of
more than two parts. Also, the cover module with drive stage may consist
of two or more parts. Also, the drive train can comprise an additional
transmission stage. Such variants will be clear to those skilled in the
art and are understood to fall within the scope of the invention as set
forth in the following claims.